Associative Learning in Invertebrates

Behaviors of invertebrates can be modified by associative learning in a similar manner to those of vertebrates. Two simple forms of associative learning, Pavlovian and operant conditioning, allow animals to establish a predictive relationship between two events. Here we summarize five decades of studies of behavioral, cellular, and subcellular changes that are induced by these two learning paradigms in different invertebrate animal models. A comparative description of circuitry, neuronal elements, and properties that contribute to these conditioning procedures will be drawn to decipher common...

Behaviors of invertebrates can be modified by associative learning in a similar manner to those of vertebrates. Two simple forms of associative learning, Pavlovian and operant conditioning, allow animals to establish a predictive relationship between two events. Here we summarize five decades of studies of behavioral, cellular, and subcellular changes that are induced by these two learning paradigms in different invertebrate animal models. A comparative description of circuitry, neuronal elements, and properties that contribute to these conditioning procedures will be drawn to decipher common and distinguishing features of the learning processes. We will illustrate that similar circuits, synaptic and neuronal membrane plasticity, and similar molecular sites of detection of association are implicated in both forms of conditioning. However, evidence will also suggest that passively responding and endogenous dynamic properties of central networks and/or their constituent neurons might differentially contribute to Pavlovian and operant learning.